Why drugs are still a scourge

"Pot Belge" sounds like something you might get after overindulging on Hoegaarden. Actually, it's a bit more potent than that. "Belgian mix", as it is generally translated, is a combination of amphetamines, cocaine and heroin. It's a cheap and dirty performance-enhancing drug for cyclists.

What's Belgian about it? Well, cycling is a huge participation sport there. All season long, you can race every day of the week on a "kermesse", a circuit race based around a village or small town. Local businesses put up the prize money, a few hundred euros. You can make a decent living even without being a full-time professional. The races are short, hard and fast; the testing regime haphazard. Hence "pot Belge": the winner's little helper.

While the Tour de France has been scandalised by revelations from Spain's "Operacion Puerto" investigation into organised drug-taking and blood- doping for pro cyclists (leading to the suspension of two Tour favourites, Ivan Basso and Jan Ullrich), the news from a Bordeaux courtroom is just as grim. A former cycling coach, Freddy Sergant, has been jailed for running a ring that supplied Belgian mix; others received fines and suspended sentences.

Giving evidence, former French pro Laurent Roux remarked that, at the top end of the sport, "Doctors cost more to hire than the riders." Much more depressing is that this sordid little drug bust shows just how far down the sport the doping problem goes - well into the amateur ranks. The pros do the hi-tech blood-doping; the aspiring amateurs ride on whizz till they can afford something better.

And "pot Belge" is not just a Belgian problem. As when syphilis appeared in the middle ages, everyone found someone else to blame - the French evil, the Spanish disease, the Neapolitans "bone-ache". The reality is that doping is universal and endemic in cycling. At least in mainland Europe.

Nobody will quite say it, but one reason why the most talented British riders never seem to realise their promise is that most stay clean. They don't come from a culture that accepts doping as the norm. The sport here is too small and there isn't enough money in it to make it worth people's while to buy the gear. Plenty of us do use legal ergogenic aids such as creatine, colostrum and sodium phosphate. I know the mentality: when you're taking supplements to boost performance, it's very easy to blur the boundaries for yourself into a morally grey continuum.

Are we so ethically superior then? I never thought I'd say this, but let's hope the sport here stays so poor that we never have to find out.

· On Your Bike! The Complete Guide to Cycling by Matt Seaton is published by Guardian Books, price £16.95.

Bike doctor

All your cycling questions answered

Dear Matt,

I am training for the "End to End" (Land's End to John O'Groats) to raise money for charity. I'm 33, have cycled all my life and am very fit. I'll be doing 85 miles a day for 12 days; I'm riding about 200 miles a week now but have started getting a lot of knee pain. I have had some physio, but the pain is ongoing. Any advice?Dave Hague, via email

Knee pain is common for most cyclists at some time - often it hits when you suddenly up the amount of work you're doing. A common cause is that the patella (kneecap) is not tracking straight because of an imbalance between the four large muscles of your quadriceps, on the top and side of your thigh. If the vastus medialis (inside) is not doing enough work, the vastus lateralis (outside) tends to take over, pulling the patella over as it rises and falls with each pedal stroke. Result: pain.

The good news: over time, the vastus medialis gets stronger and the problem sorts itself out. You can speed up the process with special exercises - ask your physio. In the meantime, cut your mileage and don't push big gears. Good luck!